In February of the New Year, the British will prepare a major celebration. It's not another Royal wedding. It's the Diamond Jubilee of Queen Elizabeth II, marking the 60th anniversary of her accession to the throne. It's an exceptionally long reign; only one other British monarch has reigned as long, her Royal Majesty Queen Victoria.

In six decades, Queen Elizabeth's reign has spanned 12 British prime ministers, 12 American presidents and six popes. She's one of the world's most famous women, instantly recognizable and eternally private.

Journalist Andrew Marr has written a new book about Queen Elizabeth II. It's called "The Real Elizabeth: An Intimate Portrait of Queen Elizabeth II," after many interviews with those closest to the Queen including her friends, advisors and her children. Andrew Marr now joins us from our studios at the BBC in London.

Andrew Marr, it's a real pleasure to have you with us.

ANDREW MARR: It's great to be talking to you, Jacki.

LYDEN: You know, it's fascinating to read through this book, a woman about what you think you know a lot, and then go into all the details - almost a pointillist picture - of how she becomes who she is. For example, we think of her as a figurehead, a unique symbol. But you say that that is really difficult job.

MARR: It's a lot harder perhaps than it looks. Every single day of the year, except for Christmas Day and sometimes Easter Day, the Queen sits down and works her way through a great, thick wodge of official papers. She reads all the most secret papers of the British state; all the stuff of the intelligence services and the rest of it. In Whitehall, they call her Reader Number One. She does that.

She travels around the world a lot, really at the behest of the British government as part of the sort of trade and diplomatic mission that goes on. She is traveling all the time around the country, going to small towns and hospitals, and police stations and so on. And she does this year in, year out.

Of course she has wonderful palaces and lots of luxury around her, but she works with truly hard.

LYDEN: And you say this stuff comes over from Whitehall in these red boxes. Everything is...

MARR: That's right.

LYDEN: ...is quite formal. So, when the Queen receives these papers each morning, what does she do with that knowledge?

MARR: That's a very good question. What she does with that is that she questions the ministers, ambassadors, above all, the prime minister. And the prime minister at the moment, David Cameron, said to me, said what's really useful for me is that I'm in all sorts of arenas and forums all the time, being asked questions. But here, once a week, in complete privacy, I'm being asked what do you really intend to do? Why have you done that? What is your thinking about this - by somebody who has great knowledge, not only of what's happening right now what happened before.

LYDEN: Reminders of how big is the realm is, the former and current realm.

MARR: Well, she's Queen of, of course, of the United Kingdom of Great Britain and Northern Ireland. But let's remember that she's Queen of Australia. She's Queen of Canada. And, indeed, as head at the Commonwealth, she's head of an organization which represents around a third of the globe's humanity.

LYDEN: She has to be the monarch at all times. She can never be spontaneous and this, too many of us, makes her appear rather stiff.

MARR: She is the exact opposite of everything in the modern age we are taught that as sort of celebrity, or a public figure, you should be. We're all encouraged to be outgoing, heart on our sleeve, emotional. If you're a public figure, people want to hear you to vivid and provocative and fresh language from you. And all of that is constitutional forbidden to the Queen.

Because if she takes a strong view about something, or says something cutting, or hurtful, or mocking or whatever, then she is speaking on behalf of the British state and that's just not acceptable. Her job is to be the figurehead.

LYDEN: Let's go back to the moment that summarizes given who the Queen is in many ways. And that is the moment that she finds out that her father is dead. She's 25 years old and she is going to ascend to the throne.

MARR: She had said goodbye to her father who was ill but didn't seem mortally ill at all. And she was in Kenya as part of what was going to be a very long tour; going off to Australia and New Zealand, in place of her father who was too ill to do that tour.

And then, suddenly this blow falls. But she didn't make a scene. She didn't complain. She simply apologized to everybody for the disruption that this was going to cause. And fact, the tour had to be canceled and wrote lots of letters of apology. And set off her - though it's said that she was crying as the plane set off for England.

And then, she landed and there waiting for her on the tarmac with great, big slightly sinister-looking official limousines clustered around the Vez(ph), Winston Churchill. There's all the senior politicians waiting for this very slight, small 25-year-old woman. From then on, she touches the tarmac; her entire life is different, her entire life is ruled by ritual and the demands of the British state.

LYDEN: You know, you write that for her this is almost like a religious vocation because she is representing, as you say, the people. So that when the different premierships or parliaments come to grief, she is there as a representative, well, of her subjects.

MARR: I think it's not an almost religious thing for her, I think it is a religious thing. I think she feels that she was God-called; that this is a religious vocation as well as a political one. Very interesting. At the time of her coronation, she insisted that it be televised and filmed against the advice of many ministers and courtiers and others.

She said no, she wanted to be crowned in sight of all her subjects. But there was one moment of the ceremony which was never filmed and never seen and that was the moment when she was anointed with oil by the archbishop and became queen. That was, if you like, the god-called moment. And I think she still regards herself quite literally as put there on behalf of all the British people by God.

And I don't think it is a metaphor for her or a simile. I think it's what she really believes.

LYDEN: Andrew Marrs' book is called "The Real Elizabeth: An Intimate Portrait of Queen Elizabeth II" comes out next week. Thank you so very much.

MARR: Thank you very much indeed for talking to me. Transcript provided by NPR, Copyright NPR.